well, spain and germany are 2 completely countries
first of all, germans typically have shorter mouths, more fuller faces, blue, green, or brown eyes, brown or blonde hair, and different shades of the colors, they also tend to have less pointed noses. and they have a peach to fair skin.
spanish on the other hand, have longer mouths, brown, hazel or green eyes. typically, they have hair ranging from light brown to an almost black. and they can have a peach, to an olive skin. men usually have more larger noses, and women have more pointed noses.
but make sure you look at the last names. german last names tend to be shorter, on the average, 2 syllables, and von and van are common ways to start a last name. Alt, zeit, schlaff are fairly common elements of a german name.
Spanish last names are simular to italian last names. usually they are longer, and use a greater amount of vowels, verses german(even though slavic languages use the most consonents.)
but to find your family, once you find out the countries, try to find out the region of the country they yeild from, and try to do some research on the residents. you can usually contact the mayor.
studying cultures, and anthropology, and my uncles research on the families history in italy